When skating on ice or snow, it is advantageous to have a skate or a ski, below referred to as vehicles, with as long a contact surface against the ice/snow as possible during the gliding phase. The skater/skier hereby becomes less sensitive to imperfections in the underlying surface and to inadequate technique. A short contact surface against the ice/snow provides advantages during quick maneuvers and push-off. Some existing technical solutions and their advantages and disadvantages are described below.
For skating on vehicles with long contact surfaces against the ice/snow, there are currently a number of technical solutions based on a so-called “clap” functionality, herein used for a ski or a skate binding were the heel or the shoe can be lifted from the vehicle or similar solutions, allowing movement between the shoe and the vehicle for a more efficient push-off. For these types of bindings the point of attachment is placed in front of the shoe or under the front part of the shoe. When the skater/skier pushes off, the heel area of the shoe releases its contact with the vehicle. This improves the power of the push-off compared to if the entire shoe is fixed to the vehicle. The push-off is however limited by the fact that the attachment point is more or less fixed. Due to the length of the vehicle's contact surface against the ice/snow, the skater/skier is forced to perform a substantial ankle movement to push-off. In order to allow this movement the skater/skier must use a shoe that is relatively soft. This leads to the support around the foot not being optimal, which affects the push-off negatively.
Bandy players play on large ice surfaces and bandy skates therefore also have a vehicle with a long contact surface against the ice. However, they are not helped by a clap functionality since they also must be able to handle quick turns. Because of the long contact surface against the ice, bandy players must be able to accomplish substantial ankle movements to achieve good push-offs. This means that the skater is forced to use a low shoe that does not provide optimal support.
Skating on vehicles with a short contact surface against the ice such as an ice hockey skate, allows for advantages in the push-off. The skater can “roll” forward on the blade and thereby achieve a longer contact time combined with application of high force against the ice, thereby achieving greater force during the push-off. Rolling forward on the blade means that the skater does not have to perform as much of a movement in the ankle, thus allowing the use of a stiffer shoe. A stiffer shoe gives more support and allows for a more powerful push-off. The short contact surface against the ice also provides for better maneuverability during sharp turns. However, a disadvantage with the short contact surface is that it glides less efficiently. This is brought about by the skater being more affected by unnecessary movements and unevenness in the underlying surface than if he would have been skating on a vehicle with a long contact surface against the ice.
A known type of binding for skates that builds upon the clap functionality is disclosed in the American patent U.S. Pat. No. 6,152,458, which shows a binding in which the shoe is attached to the upper chassis section and the skate is attached to the lower chassis section. The upper chassis section is arranged for pivotal movement around an axis, whereby the upper chassis section is arranged to be pivotal relative to the lower chassis section in the skate's longitudinal extension. The binding further allows for both the heel area and toe area of the shoe being movable during push-off when using the skate. The known binding thus shows an upper and a lower chassis interconnecting at two points. When pushing-off, the heel may be lifted at the same time as the toe area is moved backward upward. The design allows for a long push-off. However, with the known binding the skater is not able to shift the center of gravity along the length of the foot with an even pressure.
Another known type of binding for a skate that builds upon the clap functionality is disclosed in the Dutch patent application NL 8702068 A, which shows a binding in which the shoe is attached to the upper chassis section and the skate is attached to the lower chassis section. The known binding is designed to lift the heel portion of the shoe from the rear portion of the skate during push off. The coupling means has a substantial supporting function of the upper chassis in the first phase of the push off and the upper and lower contact surfaces are not in contact with each other during the whole phase of the push of, see FIG. 4 of NL 8702068. With the known binding the skater is not able to shift the center of gravity along the length of the foot with an even pressure.